Alright guys I am in the mood for doing a simple but diy type of intake on my 1999 4-cyl Accord and I have a couple of questions!

The plan is to remove the air filter housing and resonator, and simply put a cone filter at the end of the tube. I could take it a little further by removing the tube also and using a tube with the same diameter as the throttle body opening but that depends on the answer to my question#2.

Now when I was looking at the area where the resonator is seated it seems like there are a couple of holes/cavities in the bottom splash gaurd that would become open and could potentially let some water in all the way up through the hole in the chassis (the hole through which the connecting pipe between the air filter housing and resonator goes). Should I be concerned about water going in through this ?

Secondly, it looks like the throttle body opening is a good 3" or more but the intake tube tapers down to 2.5" at its filter end. Wouldn't it be better to keep a 3" diamter all through (probably the aftermarket intakes do that). Even if the intake tube has to be tapered I would imagine it should be reverse i.e wider at the filter end(more air volume capacity) and getting narrower towards the throttle body so that the velocity increases as it enters the throttle body(mixes well)??

Thanks!

 

unless you drive through 2+ feet of water don't worry about water getting in thru the little holes. you can not hydrolock your engine unless the filter is COMPLETELY submerged.

the F23 throttle body is 2.5"

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by notoriousB &raquo;</TD></TR><TR><TD CLASS="quote">
the F23 throttle body is 2.5"</TD></TR></TABLE>

Wow that was embarassing . Yes it is indeed a 2.5". I was assuming based on the tube diameter. I removed the tube and measured the mouth of the throttle body.
Boy was I shocked to see the black goo on the other side of the throttle valve/plate. Is that normal ? Should it be removed ? Is it because of the EGR gases ?

 

it's probably from the breather tube from the valve cover to the intake tube. it won't hurt to clean it off. if you do be gentle w/ the throttle plate.

 

if it was from the breather tube I would expect it to be before the throttle plate also but this is only after the plate.

I did a quick and dirty "protoype" intake by removing just the air housing (not the resonator and tube) and taping the filter to the air housing top cover all around the edges with metal duct tape typically used for sealing ductwork. Basically everything remains as-is except the bottom part of the housing. And...I am hooked! I am not going back to stock . Oh the sound of the vtec roar.

The first and most apparent thing was improved response. I dont know if this is because of gain in hp or torque or just because the engine is getting the air when it demands. I am sure there is a gain too because I can experience the difference in accelerating, passing, merging and all in regular driving. I just cant wait to go all the way with a larger cone filter, and ofcourse the resonator out of the way.